Adviesdocument voor agrariërs en overheid : "optimale verlichting van melkveestallen"

In opdracht van LTO Noord is de afgelopen maanden onderzoek gedaan naar de optimale verlichting van melkveestallen. Dit mede naar aanleiding van de discussie over dit onderwerp in de provincie Fryslân. Het doel van het onderzoek is om de mogelijkheden in kaart te brengen die gericht zijn op het terugdringen van lichtuitstoot en dit vast te leggen in een adviesdocument voor melkveehouders en beleidsmakers. Het resultaat van dit onderzoek kan enerzijds bijdragen aan een optimale stalverlichting op melkveehouderijbedrijven; anderzijds kan het ook een rol spelen bij de verbetering van de ruimtelijke kwaliteit in de provincie omdat de verlichting van agrarische gebouwen daarvan onderdeel uitmaakt. Dit onderzoek is bijzonder omdat er voor het eerst lichtmetingen bij melkveestallen zijn verricht

An international comparison of surface texture parameters quantification on polymer artefacts using optical instruments

An international comparison of optical instruments measuring polymer surfaces with arithmetic mean height values in the sub-micrometre range has been carried out. The comparison involved sixteen optical surface texture instruments (focus variation instruments, confocal microscopes and coherent scanning interferometers) from thirteen research laboratories worldwide. Results demonstrated that: (i) Agreement among different instruments could be achieved to a limited extent; (ii) standardised guidelines for uncertainty evaluation of areal surface parameters are needed for users; (iii) it is essential that the performance characteristics (and especially the spatial frequency response) of an instrument is understood prior to a measurement

Multiplication of <i>ampC</i> upon Exposure to a Beta-Lactam Antibiotic Results in a Transferable Transposon in <i>Escherichia coli</i>

Plasmids play a crucial role in spreading antimicrobial resistance genes. Plasmids have many ways to incorporate various genes. By inducing amoxicillin resistance in Escherichia coli, followed by horizontal gene transfer experiments and sequencing, we show that the chromosomal beta-lactamase gene ampC is multiplied and results in an 8–13 kb contig. This contig is comparable to a transposon, showing similarities to variable regions found in environmental plasmids, and can be transferred between E. coli cells. As in eight out of nine replicate strains an almost completely identical transposon was isolated, we conclude that this process is under strict control by the cell. The single transposon that differed was shortened at both ends, but otherwise identical. The outcome of this study indicates that as a result of exposure to beta-lactam antibiotics, E. coli can form a transposon containing ampC that can subsequently be integrated into plasmids or genomes. This observation offers an explanation for the large diversity of genes in plasmids found in nature and proposes mechanisms by which the dynamics of plasmids are maintained

Role of Interleukin 17 in arthritis chronicity through survival of synoviocytes via regulation of synoviolin expression

Background: The use of TNF inhibitors has been a major progress in the treatment of chronic inflammation. However, not all patients respond. In addition, response will be often lost when treatment is stopped. These clinical aspects indicate that other cytokines might be involved and we focus here on the role of IL-17. In addition, the chronic nature of joint inflammation may contribute to reduced response and enhanced chronicity. Therefore we studied the capacity of IL-17 to regulate synoviolin, an E3 ubiquitin ligase implicated in synovial hyperplasia in human rheumatoid arthritis (RA) FLS and in chronic reactivated streptococcal cell wall (SCW)-induced arthritis.&lt;p&gt;&lt;/p&gt; Methodology/Principal Findings: Chronic reactivated SCW-induced arthritis was examined in IL-17R deficient and wild-type mice. Synoviolin expression was analysed by real-time RT-PCR, Western Blot or immunostaining in RA FLS and tissue, and p53 assessed by Western Blot. Apoptosis was detected by annexin V/propidium iodide staining, SS DNA apoptosis ELISA kit or TUNEL staining and proliferation by PCNA staining. IL-17 receptor A (IL-17RA), IL-17 receptor C (IL-17-RC) or synoviolin inhibition were achieved by small interfering RNA (siRNA) or neutralizing antibodies. IL-17 induced sustained synoviolin expression in RA FLS. Sodium nitroprusside (SNP)-induced RA FLS apoptosis was associated with reduced synoviolin expression and was rescued by IL-17 treatment with a corresponding increase in synoviolin expression. IL-17RC or IL-17RA RNA interference increased SNP-induced apoptosis, and decreased IL-17-induced synoviolin. IL-17 rescued RA FLS from apoptosis induced by synoviolin knockdown. IL-17 and TNF had additive effects on synoviolin expression and protection against apoptosis induced by synoviolin knowndown. In IL-17R deficient mice, a decrease in arthritis severity was characterized by increased synovial apoptosis, reduced proliferation and a marked reduction in synoviolin expression. A distinct absence of synoviolin expressing germinal centres in IL-17R deficient mice contrasted with synoviolin positive B cells and Th17 cells in synovial germinal centre-like structures.&lt;p&gt;&lt;/p&gt; Conclusion/Significance: IL-17 induction of synoviolin may contribute at least in part to RA chronicity by prolonging the survival of RA FLS and immune cells in germinal centre reactions. These results extend the role of IL-17 to synovial hyperplasia.&lt;p&gt;&lt;/p&gt

The relationships between nasal hyperreactivity, quality of life, and nasal symptoms in patients with perennial allergic rhinitis

Background: A clinical test that could inform the clinician about the severity of a patient's nasal symptoms and health-related quality of life (QOL) would be very useful. Objective: We attempted to determine whether, in patients with perennial allergic rhinitis, nasal challenge with histamine could be used to estimate daily symptoms and QOL. Methods: Forty-eight patients with perennial allergic rhinitis were challenged with histamine to determine nasal hyperreactivity. Nasal response was monitored by the number of sneezes, the amount of secretion, and a symptom score. Daily nasal symptoms were recorded during the 2 preceding weeks. Patients also completed a rhinitis QOL questionnaire. Results: Responsiveness to histamine and total daily nasal symptoms were moderately correlated (r = 0.51, p = 0.001). Comparison of total daily nasal symptoms with the overall QOL score showed a moderate correlation (r = 0.59, p &lt; 0.001). Nasal response to histamine and overall QOL score were also correlated (r = 0.43, p = 0.0052). However, overall QOL and daily nasal symptoms could be predicted by wide 95% confidence intervals only for each decade of nasal responsiveness to histamine (expressed as a composite symptom score). Conclusion: In patients with perennial allergic rhinitis nasal hyperreactivity as determined by histamine challenge, QOL, and daily nasal symptoms are moderately correlated. Therefore nasal histamine challenge can be used as a tool for estimating the severity of daily nasal symptoms and QOL, although it cannot predict nasal symptoms and QOL very accurately.</p

Channelized melt flow in downwelling mantle: Implications for 226Ra-210Pb disequilibria in arc magmas

We present the results of an analytical model of porous flow of viscous melt into a steadily dilating ‘‘channel’’ (defined as a cluster of smaller veins) in downwelling subarc mantle. The model predicts the pressure drop in the mantle wedge matrix surrounding the channel needed to drive melt flow as a function of position and time. Melt is sucked toward the dilatant region at a near-constant velocity (105 s1) until veins comprising the channel stop opening (t = t). Fluid elements that complete their journey within the time span t < t arrive at a channel. Our results make it possible to calculate the region of influence sampled by melt that surrounds the channel. This region is large compared to the model size of the channelized region driving flow. For a baseline dilation time of 1 year and channel half width of 2 m, melt can be sampled over an 80-m radius and has the opportunity to sample matrix material with potentially contrasting chemistry on geologically short timescales. Our mechanical results are consistent with a downgoing arc mantle wedge source region where melting and melt extraction by porous flow to a channel network are sufficiently rapid to preserve source-derived 238U-230Th-226Ra, and potentially also 226 Ra-210Pb, disequilibria, prior to magma ascent to the surface. Since this is the rate-determining step in the overall process, it allows the possibility that such short-lived disequilibria measured in arc rocks at the surface are derived from deep in the mantle wedge. Stresses due to partial melting do not appear capable of producing the desired sucking effect, while the order of magnitude rate of shear required to drive dilation of 107 s1 is much larger than values resulting from steady state subduction. We conclude that local deformation rates in excess of background plate tectonic rates are needed to ‘‘switch on’’ the dilatant channel network and to initiate the sucking effect